Hardness and Impact Testing
Hardness and Impact Testing
(OP)
Ok, I understand hardness testing is not reaally a Code requirement, but is a measure of weld quality and is the industry (oil and gas) norm these days.
Re charpy impact testing. I have also come across requirements where impact testing is required for some weld procedures (regardless of its MDMT), especially on carbon steel and duplex ss materials. Is it also used as a "general measure" of the weld quality?
Thanks.
Re charpy impact testing. I have also come across requirements where impact testing is required for some weld procedures (regardless of its MDMT), especially on carbon steel and duplex ss materials. Is it also used as a "general measure" of the weld quality?
Thanks.





RE: Hardness and Impact Testing
Impact and hardness testing are really methods used to assure process parameters specified during fabrication have not resulted in adverse metallurgical properties.
RE: Hardness and Impact Testing
Thanks.
RE: Hardness and Impact Testing
Impact testing is really done for two reasons – to assure a minimum level of toughness for low temperature service applications of materials, and to assure that during fabrication (or welding), the material toughness does not fall below a certain minimum design metal temperature toughness specified by the code of construction.
RE: Hardness and Impact Testing
Examples of ferritic materials are carbon and low alloy steels, ferritic stainless steel - duplex stainless steels are unique because they contain a mixture of austenite and ferrite phases. Duplex stainless steels can also exhibit low toughness behavior in exposure to low temperature service or if they were not properly solution annealed.
RE: Hardness and Impact Testing